This subject matter described in this application is related to the subject matter described in co-pending U.S. application Ser. No. 11/198,996, filed Aug. 8, 2005, entitled “Geo-fencing in a Wireless Location System,” the entirety of which is hereby incorporated by reference. The aforementioned application Ser. No. 11/198,996 is a continuation of U.S. application Ser. No. 11/150,414, filed Jun. 10, 2005, entitled “Advanced Triggers for Location-Based Service Applications in a Wireless Location System,” which is a continuation-in-part of U.S. application Ser. No. 10/768,587, filed Jan. 29, 2004, entitled “Monitoring of Call Information in a Wireless Location System”, now U.S. Pat. No. 7,167,713, which is a continuation of U.S. application Ser. No. 09/909,221, filed Jul. 18, 2001, entitled “Monitoring of Call Information in a Wireless Location System,” now U.S. Pat. No. 6,782,264 B2, which is a continuation-in-part of U.S. application Ser. No. 09/539,352, filed Mar. 31, 2000, entitled “Centralized Database for a Wireless Location System,” now U.S. Pat. No. 6,317,604 B1, which is a continuation of U.S. application Ser. No. 09/227,764, filed Jan. 8, 1999, entitled “Calibration for Wireless Location System”, now U.S. Pat. No. 6,184,829 B1.
A. Wireless Location
Early work relating to Wireless Location Systems is described in U.S. Pat. No. 5,327,144, Jul. 5, 1994, “Cellular Telephone Location System,” which discloses a system for locating cellular telephones using time difference of arrival (TDOA) techniques. This and other exemplary patents (discussed below) are assigned to TruePosition, Inc., the assignee of the present invention. The '144 patent describes what may be referred to as an uplink-time-difference-of-arrival (U-TDOA) cellular telephone location system. The described system may be configured to monitor control channel transmissions from one or more cellular telephones and to use central or station-based processing to compute the geographic location(s) of the phone(s). TruePosition and others have continued to develop significant enhancements to the original inventive concepts.
B. Wireless Intelligent Networking
The wireless intelligent network (WIN) is a network architecture designed for mobile telecommunications networks. It allows operators to provide value-added services in addition to the standard telecommunications services such as call connection services on mobile phones and devices. The WIN moves service control away from the switching center (the mobile switching center or MSC) and up to a higher-level element in the network.
The WIN system is a subset of a larger family of telecommunications network services and protocols, collectively called Intelligent Networks (IN). A complete description of the IN emerged in a series of ITU-T recommendations. ITU standards defined a complete architecture including the architectural view, state machines, physical implementation and protocols. The first ITU-T series was called Capability Set One (CS-1), numbered as recommendations Q.1210 to Q.1219. The second ITU-T series was called Capability Set Two (CS-2), numbered as recommendations Q.1220 to Q.1229.
Two variants of wireless intelligent networking have evolved, loosely based on the ITU-T recommendations. Each WIN variant was developed under he auspices of a telecommunications standards setting body. The North American variant is known as Advanced Intelligent Networking (AIN) as standardized by the American National Standards Institute (ANSI). The European (and now world-wide) variant is known as Customized Applications for Mobile networks Enhanced Logic (CAMEL), as named by European Telecommunications Standards Institute (ETSI). Although both WIN standards were developed separately and the details of each protocol differ radically, the basic concepts are similar, both borrowing heavily from the ITU-T IN recommendations and both needing to satisfy the requirements of wireless operators to match competitive services offerings.
The most fundamental ability of WIN is to support remote call-processing control through a service-control function (SCF), which is basically an AIN-defined Service Control Point (SCP). When a mobile device registers with the wireless system, the wireless network will collect information over the radio interface allowing the network to register and obtain the subscriber's profile, including the subscription information from the device's Home Location Register (HLR). The subscription information includes the device's trigger detection profile (TDP), which describes the situations that will cause Intelligent Networking service logic to be invoked. In addition to triggers received from the device's HLR, the serving MSC may have its own list of static triggers to apply to all originating or terminating events.
It is these triggers which are used to define the conditions under which the AIN (SCP) or CAMEL (gsmSCF-based) external call-processing logic (the service logic) is invoked. The service logic could determine that the trigger was not really required and use a message to tell the MSC to continue processing as if the trigger never happened. This might seem redundant, but triggers are limited to general call events, resulting in “false positives”. If the WIN trigger is a general trigger, such as mobile origination, the service logic may have more complex entry criteria, allowing the call to proceed without added delay if the service entry criteria are not met.
Embodiments of the present invention use the basic WIN techniques as well as the standardized messaging and interfaces. Certain extensions to standardized triggers may be required as well as modifications to the MSC depending on the MSC vendor and/or network operator's implementation of WIN capabilities. The functionality and capabilities provided by the WIN triggers and WIN state machines may also be transferred directly to the MSC or packet-based SoftSwitch.
ANSI-WIN or AIN
The WIN capabilities developed thus far are service independent. The following three standards packages have been or are being developed by the TIA (Telecommunications Industry Association) TR-45 Engineering Committee:                Package 1 (WIN Phase I): Defines the architecture, provides the first batch of triggers and capabilities for basic call origination and call termination, and supports basic services such as Calling Name Presentation, Incoming Call Screening and Voice Controlled services. (Standards documentation has been published as TIA/EIA/IS-771).        Package 2 (WIN Phase II): Adds the second batch of triggers and capabilities, and supports Charging Services such as Prepaid, Freephone, Premium Rate, and Advice of Charging. (Standards documentation has been recommended for publication as TIA/EIA/IS-826 for Prepaid and 848 for other Charging Services).        Package 3 (WIN Phase III): Adds the third batch of triggers and capabilities, and supports Location Based Services such as Location Based Charging, Fleet and Asset Management, Location Based Information Service, and Enhanced Calling Routing. (Standard documentation is currently being under development and will be published as TIA/EIA/IS-843).        
CAMEL
The complete CAMEL detailed functionalities descriptions are described in CAMEL specifications TS 22.078 (stage 1), TS 23.078 (stage 2) and TS 29.078 (stage 3).
Phase 1—CAMEL Phase 1 defined only very basic call control services, but introduced the concept of a CAMEL Basic Call State Model (BCSM) to the Intelligent Network (IN). Phase 1 gave the gsmSCF the ability to bar calls (release the call prior to connection), allow a call to continue unchanged, or to modify a limited number of call parameters before allowing it to continue. The gsmSCF could also monitor the status of a call for certain events (call connection and disconnection), and take appropriate action on being informed of the event.
Phase 2—CAMEL Phase 2 enhanced the capabilities defined in Phase 1. In addition to supporting the facilities of Phase 1, Phase 2 included:                Additional event detection points;        Interaction between a user and a service using announcements, voice prompting and information collection via in-band interaction or Unstructured Supplementary Service Data (USSD) interaction; and        Control of call duration and transfer of Advice of Charge Information to the mobile station.        
The gsmSCF can be informed about the invocation of the supplementary services Explicit Call Transfer (ECT), Call Deflection (CD) and Multi-Party Calls (MPTY). For easier post-processing, charging information from a serving node can be integrated in normal call records.
Phase 3—The third phase of CAMEL enhanced the capabilities of Phase 2. The following capabilities were added:                Support of facilities to avoid overload;        Capabilities to support Dialed Services;        Capabilities to handle mobility events, such as (Not-)reachability and roaming;        Control of GPRS sessions and PDP contexts;        Control of Mobile Originated SMS through both circuit switched and packet switched serving network entities; and        Interworking with SoLSA (Support of Localised Service Area). Support for this interworking is optional.The gsmSCF can be informed about the invocation of the supplementary service Call Completion to Busy Subscriber (CCBS).        
Phase 4—The fourth phase of CAMEL built on the capabilities of Phase 3. The following features were defined:                CAMEL support for Optimal Routing of circuit-switched mobile-to-mobile calls;        The capability for the gsmSCF to create additional parties in an existing call (Call Party Handling);        The capability for the gsmSCF to create a new call unrelated to any other existing call (Call Party Handling—new call);        Capabilities for the enhanced handling of call party connections (Call Party Handling);        Control of Mobile Terminated SMS through both circuit switched and packet switched serving network entities;        The capability for the gsmSCF to control sessions in the IP Multimedia Subsystem (IMS); and        The gsmSCF can request the gsmSCF to play a fixed or a variable sequence of tones.        
With CAMEL Phase 4, it is possible that only a limited subset of the new functionalities is supported, in addition to the complete support of CAMEL Phase 3.
The inventive techniques and concepts described herein apply to time and frequency division multiplexed (TDMA/FDMA) radio communications systems including the widely used IS-136 (TDMA), GSM, and OFDM wireless systems, as well as code-division radio communications systems such as CDMA (IS-95, IS-2000) and Universal Mobile Telecommunications System (UMTS), the latter of which is also known as W-CDMA. The Global System for Mobile (GSM) model discussed above is an exemplary but not exclusive environment in which the present invention may be used.
Currently, denial of service at specific sites is accomplished by radio jammers. Cell phone jammers are devices that create a temporary “dead zone” to all cell phone traffic in their immediate proximity. Jammers are legally used by the police and military to control or disrupt communication during hostage situations and bomb threats. Although illegal in many countries, personal and premise cell phone jammers are increasingly available and decreasing in size and cost.